Giuseppe
Emeritus
[Source: Chest, full text: (LINK). Abstract, edited.]
------
Cytokine Activation Patterns and Biomarkers Are Influenced by Microorganisms in Community-Acquired Pneumonia
Rosario Men?ndez, PhD, Jos? Miguel Sahuquillo-Arce, MD, Soledad Reyes, MD, Raquel Mart?nez, MD, Eva Polverino, PhD, Catia Cill?niz, MD, Juan Gin?s C?rdoba, PhD, Beatriz Montull, MD and Antoni Torres, MD, PhD, FCCP
Author Affiliations: From Servicio de Neumolog?a (Drs Men?ndez, Reyes, Mart?nez, and Montull) and Servicio de Microbiolog?a (Drs Sahuquillo-Arce and C?rdoba), Hospital Universitari i Polit?cnic La Fe, Valencia; and Servei de Pneumologia (Drs Polverino, Cill?niz, and Torres), Institut del T?rax, Hospital Clinic, IDIBAPS, CIBERES, Universitat de Barcelona, Barcelona, Spain.
Correspondence to: Rosario Men?ndez, PhD, Department of Pneumology, Hospital Universitari i Polit?cnic La Fe, Bulevar Sur s/n, 46026 Valencia, Spain; e-mail: rosmenend@gmail.com
Abstract
Background: The inflammatory response in community-acquired pneumonia (CAP) depends on the host and on the challenge of the causal microorganism. Here, we analyze the patterns of inflammatory cytokines, procalcitonin (PCT), and C-reactive protein (CRP) in order to determine their diagnostic value.
Methods: This was a prospective study of 658 patients admitted with CAP. PCT and CRP were analyzed by immunoluminometric and immunoturbidimetric assays. Cytokines (tumor necrosis factor-α [TNF-α], IL-1β, IL-6, IL-8, and IL-10) were measured using enzyme immunoassay.
Results: The lowest medians of CRP, PCT, TNF-α, and IL-6 were found in CAP of unknown cause, and the highest were found in patients with positive blood cultures. Different cytokine profiles and biomarkers were found depending on cause: atypical bacteria (lower PCT and IL-6), viruses (lower PCT and higher IL-10), Enterobacteriaceae (higher IL-8), Streptococcus pneumoniae (high PCT), and Legionella pneumophila (higher CRP and TNF-α). PCT ≥ 0.36 mg/dL to predict positive blood cultures showed sensitivity of 85%, specificity of 42%, and negative predictive value (NPV) of 98%, whereas a cutoff of ≤ 0.5 mg/dL to predict viruses or atypicals vs bacteria showed sensitivity of 89%/81%, specificity of 68%/68%, positive predictive value of 12%/22%, and NPV of 99%/97%. In a multivariate Euclidean distance model, the lowest inflammatory expression was found in unknown cause and the highest was found in L pneumophila, S pneumoniae, and Enterobacteriaceae. Atypical bacteria exhibit an inflammatory pattern closer to that of viruses.
Conclusions: Different inflammatory patterns elicited by different microorganisms may provide a useful tool for diagnosis. Recognizing these patterns provides additional information that may facilitate a broader understanding of host inflammatory response to microorganisms.
Footnotes:
Funding/Support: The study was funded by Centro Investigaci?n Biomedica en Red de Enfermedades Respiratorias, an initiative of Instituto de Salud Carlos III; Sociedad Espa?ola de Neumolog?a y Cirug?a Tor?cica [Grant 2003]; Fondo de Investigaci?n Sanitario [Grant PI041136]; Fondo de Investigaci?n Sanitario [Grant PI080727]; and an IMPULSA grant.
Drs Men?ndez and Sahuquillo-Arce are considered as first authors.
Reproduction of this article is prohibited without written permission from the American College of Chest Physicians. See online for more details.
Abbreviations: CAP, community-acquired pneumonia - CRP, C-reactive protein - GNB, gram-negative bacilli - GPC, gram-positive cocci - NPV, negative predictive value - PCT, procalcitonin - TNF-α, tumor necrosis factor-α
Received June 9, 2011. Accepted November 22, 2011. 2012 American College of Chest Physicians
-Rosario Men?ndez, PhD, Jos? Miguel Sahuquillo-Arce, MD, Soledad Reyes, MD, Raquel Mart?nez, MD, Eva Polverino, PhD, Catia Cill?niz, MD, Juan Gin?s C?rdoba, PhD, Beatriz Montull, MD and Antoni Torres, MD, PhD, FCCP
Author Affiliations: From Servicio de Neumolog?a (Drs Men?ndez, Reyes, Mart?nez, and Montull) and Servicio de Microbiolog?a (Drs Sahuquillo-Arce and C?rdoba), Hospital Universitari i Polit?cnic La Fe, Valencia; and Servei de Pneumologia (Drs Polverino, Cill?niz, and Torres), Institut del T?rax, Hospital Clinic, IDIBAPS, CIBERES, Universitat de Barcelona, Barcelona, Spain.
Correspondence to: Rosario Men?ndez, PhD, Department of Pneumology, Hospital Universitari i Polit?cnic La Fe, Bulevar Sur s/n, 46026 Valencia, Spain; e-mail: rosmenend@gmail.com
Abstract
Background: The inflammatory response in community-acquired pneumonia (CAP) depends on the host and on the challenge of the causal microorganism. Here, we analyze the patterns of inflammatory cytokines, procalcitonin (PCT), and C-reactive protein (CRP) in order to determine their diagnostic value.
Methods: This was a prospective study of 658 patients admitted with CAP. PCT and CRP were analyzed by immunoluminometric and immunoturbidimetric assays. Cytokines (tumor necrosis factor-α [TNF-α], IL-1β, IL-6, IL-8, and IL-10) were measured using enzyme immunoassay.
Results: The lowest medians of CRP, PCT, TNF-α, and IL-6 were found in CAP of unknown cause, and the highest were found in patients with positive blood cultures. Different cytokine profiles and biomarkers were found depending on cause: atypical bacteria (lower PCT and IL-6), viruses (lower PCT and higher IL-10), Enterobacteriaceae (higher IL-8), Streptococcus pneumoniae (high PCT), and Legionella pneumophila (higher CRP and TNF-α). PCT ≥ 0.36 mg/dL to predict positive blood cultures showed sensitivity of 85%, specificity of 42%, and negative predictive value (NPV) of 98%, whereas a cutoff of ≤ 0.5 mg/dL to predict viruses or atypicals vs bacteria showed sensitivity of 89%/81%, specificity of 68%/68%, positive predictive value of 12%/22%, and NPV of 99%/97%. In a multivariate Euclidean distance model, the lowest inflammatory expression was found in unknown cause and the highest was found in L pneumophila, S pneumoniae, and Enterobacteriaceae. Atypical bacteria exhibit an inflammatory pattern closer to that of viruses.
Conclusions: Different inflammatory patterns elicited by different microorganisms may provide a useful tool for diagnosis. Recognizing these patterns provides additional information that may facilitate a broader understanding of host inflammatory response to microorganisms.
Footnotes:
Funding/Support: The study was funded by Centro Investigaci?n Biomedica en Red de Enfermedades Respiratorias, an initiative of Instituto de Salud Carlos III; Sociedad Espa?ola de Neumolog?a y Cirug?a Tor?cica [Grant 2003]; Fondo de Investigaci?n Sanitario [Grant PI041136]; Fondo de Investigaci?n Sanitario [Grant PI080727]; and an IMPULSA grant.
Drs Men?ndez and Sahuquillo-Arce are considered as first authors.
Reproduction of this article is prohibited without written permission from the American College of Chest Physicians. See online for more details.
Abbreviations: CAP, community-acquired pneumonia - CRP, C-reactive protein - GNB, gram-negative bacilli - GPC, gram-positive cocci - NPV, negative predictive value - PCT, procalcitonin - TNF-α, tumor necrosis factor-α
Received June 9, 2011. Accepted November 22, 2011. 2012 American College of Chest Physicians
------